The present invention relates generally to improvements in explosion containment, and more particularly pertains to an explosion containment device for stored explosives.
One of the more critical problems confronting developers of explosion containment devices has been redirected blast pressure. In Dill, U.S. Pat. No. 2,818,808 and Neal, U.S. Pat. No. 2,655,619, acoustical reflection plates or barriers are used between shaped charges so as to reduce the magnitude of the pressure wave traveling from one charge to the other upon the detonation of one of the charges. Recognizing that any explosion generates a pressure wave which travels out from the center of the explosion in all directions, any part of a pressure wave which is redirected, as through the use of a reflection plate, combines with the unredirected portions of the pressure wave to create an even greater pressure in a direction away from the reflection plate. This redirected, vastly increased pressure wave may create an even greater problem than the sympathetic detonation of other explosive units within the same area. In fact, redirected blast pressure from a single artillery shell may be much more devastating than the combined blast pressure of a plurality of artillery shells which are simultaneously detonated but whose blast pressure wave is unconfined. In effect then, the solving of one problem has created another equally perplexing and potentially more serious problem.
Another method of packaging explosive units so as to prevent sympathetic detonations is illustrated in Banta, U.S. Pat. No. 3,757,933, which discloses a box containing a plurality of hollow tubes with explosive units slidably set within the tubes. Frangible areas are carried by portions of two opposite walls of the box proximate the ends of the tubes, so as to permit a rapid release of the redirected explosive gases generated upon a single premature detonation. In this way, the adjacent explosive units are isolated from residual shock waves that would otherwise trigger sympathetic detonations, but the problem of redirected blast pressure is not solved. With such a device, great care must be taken to insure that areas which may be subjected to the redirected blast pressure are not used for storage of explosive units or other damageable materials.
While the aforementioned patents all rely upon steel members which by sheer strength are used to redirect blast pressure away from adjacent explosive units, thus ignoring the problem of redirected blast pressure, other prior art systems have attempted to deal both with the problem of sympathetic detonation and redirected blast pressure. For example, Benedick et al, U.S. Pat. No. 4,055,247 and Tabor, U.S. Pat. No. 3,786,956, disclose systems directed to the containment of individual explosive units in storage containers which are designed to both absorb and contain the blast, fragments and detonation products from a possible detonation of a contained explosive. Both of these systems rely upon very large bulky containers which are designed to be elastic in nature and which stretch and expand upon detonation, thereby reducing the momentum of the detonation products and high velocity fragments. Of course, containers of these types cannot be used with conventional artillery shell storage means, such as when artillery shells are loaded and stored on pallets. Use of such containment devices are totally impractical in military field operations due to the large number of vehicles that would be required to transport even a minimal number of artillery shells, as well as the amount of time which would be required to extricate an artillery shell from one of these containers and the amount of storage space which would be required to store a sufficient number of shells.